Adsorption dryers are generally designed in a cold regenerating manner and have been in use for a long time. Of two adsorber containers or cartridges filled with desiccating agent, one adsorber container dries the gas flow supplied via the control head by means of adsorption, while the other adsorber container regenerates the desiccating agent with a regeneration gas flow. As a rule, a partial flow of the dried gas flow depressurised to ambient pressure is used as the regeneration gas flow. The duration of the regeneration phase approximately corresponds to the duration of the adsorption phase whereby the regeneration phase is divided into an active regeneration phase with a flow of regeneration air and a passive regeneration phase without a flow of regeneration air.
Before reaching the intake capacity of the desiccating agent, with the aid of switching valves the fluid flows are switched over which exchanges the functions of both adsorber containers. This means that both containers switch between adsorption and regeneration and therefore also between operating pressure and ambient pressure.
The normally used desiccating agent only has a limited lifespan so that replacement is unavoidable. The lifespan of the desiccating agent is primarily dependent on the local operating conditions. The replacement of the desiccating agent and, depending on the design of the adsorption dryer, also of other operating means or the entire control head is laborious and requires specialist knowledge. For example, when filling with desiccating agent it is important that the adsorber containers are uniformly and compactly filled with desiccating agent in order to prevent any movement of the individual spherules of the desiccating agent when the gas to be dried flows through. This prevents inadmissible wear and the formation of open flow channels.
An adsorption dryer of this type is described in DE 103 55 928 A1. In this dryer two adsorber containers can be used in one control head so that after detaching the adsorber containers the control head can remain in place in the fluid system via the pipe connections. All the valves are arranged in the control head and can, if necessary, be separately exchanged. The adsorber containers are each formed by a housing that has a base, a container casing and a cover. The desiccating agent is contained in the adsorber container, or alternatively a desiccating agent cartridge can be inserted. The adsorber container and the control head are screwed together by way of an internal thread on the adsorber containers and an external thread arranged on the control head. In order to ensure a defined fluid supply a container head is envisaged as a further component which is inserted between an adsorber container and the control head. It is described as being advantageous that before screwing on the adsorber container the container head must be preassembled on the fixed section so that it is held in the correct position there. Pressure tightness is brought about by screwing on the adsorber container.